NAME¶
ddrescue - data recovery tool
SYNOPSIS¶
ddrescue [
options]
infile outfile [
logfile]
DESCRIPTION¶
GNU ddrescue - Data recovery tool. Copies data from one file or block device to
another, trying to rescue the good parts first in case of read errors.
You should use a logfile unless you know what you are doing. If you reboot,
check the device names before restarting ddrescue. Do not use options '-F' or
'-G' without reading the manual first.
OPTIONS¶
- -h, --help
- display this help and exit
- -V, --version
- output version information and exit
- -a, --min-read-rate=<bytes>
- minimum read rate of good areas in bytes/s
- -A, --try-again
- mark non-trimmed, non-scraped as non-tried
- -b, --sector-size=<bytes>
- sector size of input device [default 512]
- -B, --binary-prefixes
- show binary multipliers in numbers [SI]
- -c, --cluster-size=<sectors>
- sectors to copy at a time [128]
- -C, --complete-only
- do not read new data beyond logfile limits
- -d, --direct
- use direct disc access for input file
- -D, --synchronous
- use synchronous writes for output file
- -e, --max-errors=[+]<n>
- maximum number of [new] error areas allowed
- -E, --max-error-rate=<bytes>
- maximum allowed rate of read errors per second
- -f, --force
- overwrite output device or partition
- -F, --fill-mode=<types>
- fill given type blocks with infile data (?*/-+)
- -G, --generate-mode
- generate approximate logfile from partial copy
- -H, --test-mode=<file>
- set map of good/bad blocks from given logile
- -i, --input-position=<bytes>
- starting position of domain in input file [0]
- -I, --verify-input-size
- verify input file size with size in logfile
- -K, --skip-size=<min>[,<max>]
- initial size to skip on read error [64 KiB]
- -L, --loose-domain
- accept an incomplete domain logfile
- -m, --domain-logfile=<file>
- restrict domain to finished blocks in file
- -M, --retrim
- mark all failed blocks as non-trimmed
- -n, --no-scrape
- skip the scraping phase
- -N, --no-trim
- skip the trimming phase
- -o, --output-position=<bytes>
- starting position in output file [ipos]
- -O, --reopen-on-error
- reopen input file after every read error
- -p, --preallocate
- preallocate space on disc for output file
- -P, --data-preview[=<lines>]
- show some lines of the latest data read [3]
- -q, --quiet
- suppress all messages
- -r, --retry-passes=<n>
- exit after <n> retry passes (-1=infinity) [0]
- -R, --reverse
- reverse the direction of all passes
- -s, --size=<bytes>
- maximum size of input data to be copied
- -S, --sparse
- use sparse writes for output file
- -t, --truncate
- truncate output file to zero size
- -T, --timeout=<interval>
- maximum time since last successful read
- -u, --unidirectional
- run all passes in the same direction
- -v, --verbose
- be verbose (a 2nd -v gives more)
- -w, --ignore-write-errors
- make fill mode ignore write errors
- -x, --extend-outfile=<bytes>
- extend outfile size to be at least this long
- -X, --exit-on-error
- exit after the first read error
- -1, --log-rates=<file>
- log rates and error sizes in file
- -2, --log-reads=<file>
- log all read operations in file
- --ask
- ask for confirmation before starting the copy
- --cpass=<n>[,<n>]
- select what copying pass(es) to run
- --pause=<interval>
- time to wait between passes [0]
Numbers may be in decimal, hexadecimal or octal, and may be followed by a
multiplier: s = sectors, k = 1000, Ki = 1024, M = 10^6, Mi = 2^20, etc... Time
intervals have the format 1[.5][smhd] or 1/2[smhd].
Exit status: 0 for a normal exit, 1 for environmental problems (file not found,
invalid flags, I/O errors, etc), 2 to indicate a corrupt or invalid input
file, 3 for an internal consistency error (eg, bug) which caused ddrescue to
panic.
REPORTING BUGS¶
Report bugs to bug-ddrescue@gnu.org
Ddrescue home page:
http://www.gnu.org/software/ddrescue/ddrescue.html
General help using GNU software:
http://www.gnu.org/gethelp
COPYRIGHT¶
Copyright © 2014 Antonio Diaz Diaz. License GPLv2+: GNU GPL version 2 or
later <
http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it. There is NO
WARRANTY, to the extent permitted by law.
SEE ALSO¶
The full documentation for
ddrescue is maintained as a Texinfo manual. If
the
info and
ddrescue programs are properly installed at your
site, the command
- info ddrescue
should give you access to the complete manual.